BUDAPEST, Hungary — The leader of Hungary's largest opposition party on Sunday told thousands of supporters that he would guide his country out of its international isolation if he defeats Prime Minister Viktor Orbán in elections scheduled for next year.

Péter Magyar, the leader of the Respect and Freedom (Tisza) party, represents the most serious challenge to Mr. Orbán's power since the right-wing populist leader took power in 2010. Recent polling suggests that Tisza has overtaken Mr. Orbán's Fidesz party as Hungary struggles with a stagnating economy and has been politically sidelined in the European Union over Mr. Orbán's policies.

Speaking at a rally in Budapest on Sunday, Magyar said that, if elected, he and his party would restore Hungary's relationships and reputation among its allies that have suffered as Orbán has attacked the European Union and pursued close relationships with autocracies like Russia and China.

“We will finally put our common affairs in order,” Mr. Magyar said. "Our homeland, Hungary, will once again be a proud and reliable ally of NATO. Hungary will once again be a full-fledged member of the European Union.”

Mr. Orbán, a self-described “illiberal” leader, has been accused by critics of having led Hungary out of the community of European democracies by eroding democratic institutions, violating judicial independence and taking over much of Hungary's media.

Since taking power in 2010, he and his Fidesz party have led the country with a two-thirds majority in parliament, and easily defeated any opposition.

But recent polls suggest that Tisza has pulled ahead of Fidesz in popularity as Mr. Magyar's campaign focuses on economic and social issues facing the country like persistent inflation, a poor healthcare system and alleged government corruption.

On Sunday, Mr. Magyar said Mr. Orbán's system “cannot be reformed, cannot be fixed, cannot be improved. This system can only be replaced, and that is what we will do — lawfully, democratically, but with determination, we will cut down the regime.”

Nóra Farkas, a supporter of Mr. Magyar at the rally, said she had hoped for Mr. Orbán's defeat in Hungary's last national elections in 2022, but that with around a year to go before the next ballot, she is more confident that change is possible.

“Anyone who thinks things are going well in this country is blind. Mr. Orbán and his circle are the main reason for the problems," she said.

First Published: April 13, 2025, 8:49 p.m.
Updated: April 14, 2025, 2:01 a.m.